Open-Kronos: a model-checker for timed (Buchi) automata

Open-Kronos was built around 1997 as a successor to
Kronos.
The main objectives have been, on one hand, to endow Kronos with a
more convenient modeling language (e.g., with discrete variables)
and, on the other hand, to have an "open" software architecture
where users could contribute their model-checking algorithms.

For this, Open-Kronos was based on the
SMI tool built by Marius Bozga,
for symbolic model-checking discrete systems.
SMI, in turn, uses some libraries from CADP.

In the meantime, a large part of the technology used in both SMI and
Open-Kronos has been transfered to the successor tool
IF.
However, there are still a few algorithms in Open-Kronos which have not
been transfered to IF, in particular those implemented in the module
Profounder.
Profounder is able of checking reachability of timed automata and
emptiness of timed Buchi automata. It can produce concrete timed
traces in the first case.
Profounder is a powerful tool. For instance, full DFS can explore 10 million states and
15 million transitions in less than 30 seconds (measured on a
Xeon 2,8Ghz machine with 512MB RAM running Linux i686).

Profounder implements a number of algorithms,
including standard depth-first search (DFS), "full" DFS (keep only
a stack but no set of visited nodes), the "double" DFS algorithm
of paper [1] below for (timed) Buchi automata emptiness, etc.
These algorithms are run on the so-called "simulation" graph of the
timed-automaton model, the same graph used for reachability.
The theory behind all this can be found in the paper [2].

Profounder is available free of charge for academic use.
Note that in order to be able to use Profounder, you must first obtain
CADP.
To receive Profounder, email me at
Stavros.Tripakis@imag.fr, and also: print the distribution
license, then fill it in and post it to